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The conjugacy relation plays an important role in group theory and the conjugacy relation of groups has been generalized to semigroups in various methods by several authors. If a a and b b are elements of a semigroup S S , then a a is called primarily conjugate to b b if a = u v a=uv and b = v u b=vu for some u , v ∈ S 1 u,v\in {S}^{1} . In general, primary conjugacy is reflexive and symmetric, but not transitive. Finding the classes of semigroups in which the primary conjugacy is transitive is an open problem raised by Araújo et al. in the literature. In this article, among other things we prove that the primary conjugacy is transitive in regular ω \omega -semigroups.

Acetylcholinesterase (AChE) is a key enzyme used to detect organophosphorus pesticide residues by the enzyme inhibition method. An accidental discovery of a mutant strain with AChE activity was made in our laboratory during the process of AChE expression by Pichia pastoris. The pPIC9K-Drosophila melanogaster acetylcholinesterase (DmAChE)-like expression vector was constructed by codon optimization of this mutant strain, which was transformed into P. pastoris GS115, and positive clones were selected on yeast peptone dextrose (YPD) plate with G418 at 4.0 mg/mL. The GS115-pPIC9K-DmAChE-like strain was subjected to 0.5% methanol induction expression for 120 h, with a protein band at 4.3 kDa found by the tricine-sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) pattern of the fermentation supernatant. After preliminary purification by ammonium sulfate precipitation, the enzyme activity was detected to be 76.9 U/(mL⋅min). In addition, the pesticide sensitivity test proved that DmAChE-like is selective and sensitive to organophosphorus pesticides.

Let X X be a non-empty set and Y Y a non-empty subset of X X . Denote the full transformation semigroup on X X by T ( X ) T\left(X) and write f ( X ) = { f ( x ) ∣ x ∈ X } f\left(X)=\{f\left(x)| x\in X\} for each f ∈ T ( X ) f\in T\left(X) . It is well known that T ( X , Y ) = { f ∈ T ( X ) ∣ f ( X ) ⊆ Y } T\left(X,Y)=\{f\in T\left(X)| f\left(X)\subseteq Y\} is a subsemigroup of T ( X ) T\left(X) and R T ( X , Y ) RT\left(X,Y) , the set of all regular elements of T ( X , Y ) T\left(X,Y) , also forms a subsemigroup of T ( X , Y ) T\left(X,Y) . Green’s ∗ \ast -relations and Green’s ∼ \sim \hspace{0.08em} -relations (with respect to a non-empty subset U U of the set of idempotents) were introduced by Fountain in 1979 and Lawson in 1991, respectively. In this paper, we intend to present certain characterizations of these two sets of Green’s relations of the semigroup T ( X , Y ) T\left(X,Y) . This investigation proves that the semigroup T ( X , Y ) T\left(X,Y) is always a left Ehresmann semigroup, and R T ( X , Y ) RT\left(X,Y) is orthodox (resp. completely regular) if and only if Y Y contains at most two elements.

The maturity of 5G technology has promoted the rapid development of vehicular communications and intelligent transportation systems. As an important part of vehicular communications, vehicle-to-infrastructure (V2I) is used for the huge data transmission between vehicles and roadside units. Aiming to analyse the V2I wireless channel distance-dependent characteristics, this study presents two 5.9 GHz measurements in urban and suburban propagation scenarios. The distance-based amplitude distribution, delay and Doppler spreads, path loss and shadowing are extracted from the raw data. It is noted that the characteristics of V2I wireless channel vary with the distance between the transmitter and receiver. Rich multi-path components in the urban area will make more influence than that in the suburban area. Similar with the 5G pico-cell, the coverage distance, signal-to-noise ratio and channel capacity are calculated from the measurement data. The proposed results indicate that the coverage ranges of urban and suburban V2I wireless communication are about 250.3 and 80.04 m when the average power received from a single reference signal is − 85 dB . Rich reflection effect from surroundings in the urban propagation scenario will lead to a faster attenuation of wireless signal. The proposed results can provide a meaningful reference for future research of 5G vehicular communications.

To guarantee shipping safety, it is crucial to build a reliable wireless communication network. This study presents characteristic analysis of shipping wireless channel based on measurements. The authors conduct five channel measurements for two important water mobile communications, covering inland river and sea scenarios. Channel characteristics, e.g. power delay profile, amplitude distribution, delay spread and shadow fading, are extracted and compared for the two scenarios. It is found that the main difference between the them lies in more obstacles and scatterers in inland river propagation environment. The results show that more obstacles and scatterers can result in richer multipath effect and larger shadow fading decorrelation distance. A triple Gaussian mixture distribution (TGMD) is proposed to characterize the wireless channel with LOS, obstructed LOS and non-LOS situations in the practical propagation. To verify the effectiveness of TGMD, the goodness of fit between measurement and analysis results in terms of Rician K-factor, root mean square (RMS) delay spread and RMS Doppler spread is calculated. Furthermore, the cross-correlation among shadow fading, Rician K-factor and RMS delay spread are studied. Larger cross-correlation can be found in inland river and sea than vehicular communication due to the open propagation environment.

BACKGROUND: Human epidermal growth factor receptor 2 (HER2)‐mutant lung cancer remains an orphan of specific targeted therapy. The variable responses to anti‐HER2 therapies in these patients prompt us to examine impact of HER2 variants and co‐mutations on responses to anti‐HER2 treatments in lung cancer. PATIENTS AND METHODS: Patients with stage IV/recurrent HER2‐mutant lung cancers identified through next‐generation sequencings were recruited from seven hospitals. The study comprised a cohort A to establish the patterns of HER2 variants and co‐mutations in lung cancer and a cohort B to assess associations between HER2 variants, co‐mutations, and clinical outcomes. RESULTS: The study included 118 patients (cohort A, n = 86; cohort B, n = 32). Thirty‐one HER2 variants and 35 co‐mutations were detected. Predominant variants were A775_G776insYVMA (49/118, 42%), G778_P780dup (11/118, 9%), and G776delinsVC (9/118, 8%). TP53 was the most common co‐mutation (61/118, 52%). In cohort B, objective response rates with afatinib were 0% (0/14, 95% confidence interval [CI], 0%–26.8%), 40% (4/10, 14.7%–72.6%), and 13% (1/8, 0.7%–53.3%) in group 1 (A775_G776insYVMA, n = 14), group 2 (G778_P780dup, G776delinsVC, n = 10), and group 3 (missense mutation, n = 8), respectively (p = .018). Median progression‐free survival in group 1 (1.2 months; 95% CI, 0–2.4) was shorter than those in group 2 (7.6 months, 4.9–10.4; hazard ratio [HR], 0.009; 95% CI, 0.001–0.079; p < .001) and group 3 (3.6 months, 2.6–4.5; HR, 0.184; 95% CI, 0.062–0.552; p = .003). TP53 co‐mutations (6.317; 95% CI, 2.180–18.302; p = .001) and PI3K/AKT/mTOR pathway activations (19.422; 95% CI, 4.098–92.039; p < .001) conferred additional resistance to afatinib. CONCLUSION: G778_P780dup and G776delinsVC derived the greatest benefits from afatinib among HER2 variants. Co‐mutation patterns were additional response modifiers. Refining patient population based on patterns of HER2 variants and co‐mutations may help improve the efficacy of anti‐HER2 treatment in lung cancer. IMPLICATIONS FOR PRACTICE: Human epidermal growth factor receptor 2 (HER2)‐mutant lung cancers are a group of heterogenous diseases with up to 31 different variants and 35 concomitant genomic aberrations. Different HER2 variants exhibit divergent sensitivities to anti‐HER2 treatments. Certain variants, G778_P780dup and G776delinsVC, derive sustained clinical benefits from afatinib, whereas the predominant variant, A775_G776insYVMA, is resistant to most anti‐HER2 treatments. TP53 is the most common co‐mutation in HER2‐mutant lung cancers. Co‐mutations in TP53 and the PI3K/AKT/mTOR pathway confer additional resistance to anti‐HER2 treatments in lung cancer. The present data suggest that different HER2 mutations in lung cancer, like its sibling epidermal growth factor receptor, should be analyzed independently in future studies.

Silver nanoparticles (Ag NPs) have been deposited on the surface of cotton fabrics by a facile two-step method involving liquid precipitation and dielectric barrier discharge (DBD) cold plasma reduction. X-ray diffraction, X-ray photoelectron spectroscopy and high-resolution TEM show that Ag exists only in the metallic state form on the surface of the cotton fibers after DBD plasma treatment, demonstrating that DBD plasma is a promising technique for metallic oxide in situ reduction. The Ag NPs-modified cotton fabrics exhibit the significant antibacterial property against both Escherichia coli and Staphylococcus aureus, which have potential applications in the healthcare and medicine fields.

For a long time, the development of maritime communication has been restricted by the low data rate, high-latency and high cost of the current communication systems. The upgrade of new generation mobile communication technologies is attracting more and more attention to conduct a shore-based broadband mobile communication network with high-latency and high reliability to serve the maritime industries. This paper presents a solution by means of building a ship-to-infrastructure (S2I) and a ship-to-ship (S2S) wireless communication networks for an offshore region. We characterize the S2I and S2S channels at 5.9 GHz band based on the channel measurements in realistic environments. The channel characteristics, including power delay profile, delay spread, propagation path loss, are extracted and analyzed. In view of the difference between marine and terrestrial communications, we analyze the influencing factors of the offshore water, including effective reflection, divergence and shadowing from the water surface, and diffraction loss caused by the earth curvature. We also predict the power coverage range and the channel capacity for S2I and S2S wireless communications. Finally, the communication performance is evaluated according to the channel measurement and characterization analysis. The research results can be a reference for the construction of maritime communication networks.

Objective: To determine the expression of tyrosine protein kinase Met (c-MET), epidermal growth factor receptor (EGFR), and human epidermal growth factor receptor 2 (HER-2) in cases with gastric adenocarcinoma (GA). Methods: The positive rates of the c-MET, EGFR, and HER-2 proteins between cancerous tissues and normal tissues sampled from 87 patients with GA were compared. The patients were assigned to different subgroups according to their clinicopathological characteristics and analyzed. Then the relationship between the above three indexes and the positive expression of Ki-67 were analyzed. In addition, the patients were assigned to positive and negative groups based on the situation of c-MET, EGFR and HER-2 proteins, and followed up for three years. These groups were compared in terms of recurrence-free survival, overall survival, and risks factors of prognosis. Results: The positive rates of c-MET, EGFR and HER-2 proteins in GA tissues were all higher than those in corresponding non-tumor tissues (all P

The aim of the present study was to investigate the neuroprotective effects of naringin on the memory impairment of hydrocortisone mice, and to elucidate the potential underlying molecular mechanisms. In the present study, a hydrocortisone model was constructed. Novel object recognition, Morris water maze and step‑down tests were performed in order to assess the learning and memory abilities of mice. Hematoxylin and eosin staining was used to observe pathological changes in the hippocampus and hypothalamus. Transmission electron microscopy was used to observe the ultrastructural changes in the hippocampus. Immunohistochemistry was used to detect the expression of ERα and ERβ. Western blotting was performed to detect the expression of each protein in the relevant system. It was found that naringin can significantly improve cognitive, learning and memory dysfunction in mice with hydrocortisone memory impairment. In addition, naringin can exert neuroprotective effects through a variety of mechanisms, including amyloid β metabolism, Tau protein hyperphosphorylation, acetylcholinergic system, glutamate receptor system, oxidative stress and cell apoptosis. Naringin can also affect the expression of phosphorylated‑P38/P38, indicating that the neuroprotective effect of naringin may also involve the MAPK/P38 pathway. The results of the present study concluded that naringin can effectively improve the cognitive abilities of mice with memory impairment and exert neuroprotective effects. Thus, naringin may be a promising target drug candidate for the treatment of Alzheimer's disease.

This study aims to determine outcomes and complications in functional reconstruction of soft tissue defects after surgical resection for soft tissue sarcomas (STSs) of extremities.A retrospective chart review was performed on patients with STSs of extremities from May 2015 to April 2019 who underwent radical resection of STSs and reconstruction of soft tissue defect with free vascularized anterolateral thigh flap (FVALTP). A minimum 3-month follow-up was required for all the patients. Patient demographics and comorbidities, flap characteristics, postoperative complications, and time to heal were recorded. The functional outcomes of the reconstructed limbs were assessed by the Musculoskeletal Tumour Society（MSTS） scoring system.A total of 11 patients (four males and seven females) were included in the study. The mean age was 62 years (range: 29-84 years). The mean surface area was 151.4 cmFVALTP technique can be effectively applied to the reconstruction of soft tissue defect after STSs resection. The short-term follow-up indicated satisfactory functional outcome and low incidence of previously known complications. It was necessary to further validate its efficacy in reconstruction of soft tissue defect after malignant extremity soft tissue sarcoma resection.

Fusarium graminearum is a destructive wheat pathogen. No fully resistant cultivars are available. Knowledge concerning the molecular weapons of F. graminearum to achieve infection remains limited. Here, we report that deletion of the putative secondary metabolite biosynthesis gene cluster fg3_54 compromises the pathogen’s ability to infect wheat through cell-to-cell penetration. Ectopic expression of fgm4, a pathway-specific bANK-like regulatory gene, activates the transcription of the fg3_54 cluster in vitro. We identify a linear, C- terminally reduced and d-amino acid residue-rich octapeptide, fusaoctaxin A, as the product of the two nonribosomal peptide synthetases encoded by fg3_54. Chemically-synthesized fusaoctaxin A restores cell-to-cell invasiveness in fg3_54-deleted F. graminearum, and enables colonization of wheat coleoptiles by two Fusarium strains that lack the fg3_54 homolog and are nonpathogenic to wheat. In conclusion, our results identify fusaoctaxin A as a virulence factor required for cell-to-cell invasion of wheat by F. graminearum., Fusarium graminearum is a fungal pathogen of wheat and other cereals. Here the authors identify a gene cluster in F. graminearum encoding the production of a non-ribosomal peptide that is required for infection of wheat through cell-to-cell penetration.

We herein report the functionalization of α-C–H in alcohols through cross-dehydrogenative coupling reactions. Selectfluor was used as a mild oxidant. In situ-generated HF participated in the reaction and no external strong acid was necessary. A variety of heteroaryl-substituted alcohols were achieved with good yields and with good functional group tolerance.

The reaction of trifluoromethylated tertiary bromides with isonitriles induced by visible light is reported. Defluorination was avoided in a radical process. This method provides an efficient approach to compounds containing a trifluoromethylated quaternary carbon center, most of which show excellent potential to be agrochemicals. In addition, the bromides were prepared from perfluoroisobutylene, which is a waste from industry, after several steps. This reaction shows a feasible transfer of harmful waste into useful compounds.

Background: The role of Methylene tetrahydrofolate reductase (MTHFR) C677T and A1298C polymorphisms in the efficacy and toxicity of MTX-based therapy remains uncertain. Our purpose was to clarify whether these two polymorphisms are associated with the outcome of chemotherapy in a cohort of Chinese osteosarcoma (OS) patients treated by high-dose MTX. Methods: 109 OS patients who had sequentially received high-dose MTX therapy were included in this study. Plasma MTX level was measured routinely at 0, 24, 48 and 72 h after the administration of MTX. Two variants of MTHFR were genotyped using TaqMan SNP Genotyping Assay, including rs1801133 (C667T) and rs1801131 (A1298C). The extent of toxicity induced by MTX, including hematological toxicity, hepatic toxicity, renal toxicity and mucositis, was scored from grade 1 to 4. Severe toxicity was defined as a grade score of ≥3. Patients were dichotomized as follows: grade 0.2 µmol/L for plasma MTX level at 72 h. The frequencies of genotypes and allele were compared between the dichotomized groups with the Chi-square test. Results: 24.8% (27/109) of the patients were found to have significantly high plasma MTX level at the 72 h. Patients with high MTX level at 72 h were found to have significantly higher frequency of genotype TT of rs1801133 (p = 0.002). As for rs1801131, no significant association was found with plasma MTX level. Patients with severe hepatic toxicity or mucositis were found to have remarkably higher incidence of genotype TT of rs1801133 than those with mild toxicity (33.3% vs. 14.8%, p = 0.04 for hepatic toxicity; 34.8% vs. 19.8%, p = 0.05 for mucositis). Conclusions: Variant rs1801133 was confirmed to have remarkable influence on the MTX-induced toxicity. We recommend identification of the genotype of MTHFR variant prior to the application of high-dose MTX to OS patients, which could be an important predictor to screen severe toxicities and thus improve treatment outcomes. Keywords: Osteosarcoma, MTX, Variants, MTHFR, Toxicity

Zitao Zhang,1 Polu Hu,2 Jin Xiong,1 Shoufeng Wang1 1Department of Orthopedics, The Affiliated Drum Tower Hospital of Nanjing University Medical School, Nanjing 210008, China; 2Nanjing Red Cross Blood Center, Nanjing 210003, China Background: GIT1, a scaffold protein with ubiquitous multi-domain, is involved in many cellular processes. In recent years, it was proved that GIT1 participated in various tumors’ growth or metastasis. However, the biological function of GIT1 in osteosarcoma is still unclear. In this study, we aimed to investigate the role and mechanism of GIT1 in osteosarcoma.Materials and methods: Human osteosarcoma tissues were obtained to investigate the distribution of GIT1. Adequate osteosarcoma cells were stably infected with lentivirus to knockdown GIT1 level and then was used to carry out cell invasion and vascular endothelial growth factor (VEGF) assay in vitro. Orthotopic femoral osteosarcoma model was constructed to investigate the growth, invasion, and angiogenesis in vivo. Western blot was used to detect extracellular signal-regulated kinase (ERK1/2) activation and hypoxia-inducible factor-1 (HIF-1α) expression.Results: In this study, we found that GIT1 was distributed in human osteosarcoma tissues and highly expressed in osteosarcoma (OS) cells. Knockdown of GIT1 inhibited cell invasion and VEGF release in vitro and suppressed tumor growth, invasion, and angiogenesis in vivo. Furthermore, knockdown of GIT1 substantially downregulated the protein levels of p-ERK and HIF-1α in OST cells and inhibition of p-ERK by PD98059 could significantly decrease the expression of HIF-1α and concentration of VEGF in GIT1-shRNA-treated cells.Conclusion: GIT1 knockdown can effectively inhibit the growth, invasion, and angiogenesis of osteosarcoma. Thus, GIT1 might act as an oncogenic factor in osteosarcoma and could be a potential molecular target for osteosarcoma gene therapy. Keywords: GIT1, osteosarcoma, angiogenesis, orthotopic femoral osteosarcoma model, ERK1/2, HIF-1&alpha

NUT carcinoma (NC) is an aggressive squamous tumor characterized by NUT gene rearrangement, and the most common fusion form is BRD4-NUT. However, NC diagnosis is difficult for its rareness and often being confused with a variety of poorly differentiated tumors. A 21-year-old Chinese woman was referred to our hospital for cough and intermittent fever. Chest computed tomography (CT) imaging revealed a left lobe hilar mass. Fiberoptic bronchoscopy results showed that tumor cells were poorly differentiated. In combination with immunohistochemistry staining, she was misdiagnosed with Ewing’s sarcoma/primitive neuroectodermal tumor. Next-generation sequencing (NGS) revealing BRD4-NUT fusion, and NUT immunohistochemistry confirmed the diagnosis of NC. Subsequently, left pneumonectomy and lymph node dissection were performed, and the patient received pemetrexed and lobaplatin treatment. NGS technology played an important role in NC diagnosis in this case, and it may have clinical use for rare cancer diagnosis and guidance of potential targeted therapies.

The molecular mechanisms underlying the development of osteosarcoma (OS) are not fully understood. In this study, we investigated for the first time the clinical significance and biological activity of centrosomal protein 55 (CEP55) in OS. We found that CEP55 was overexpressed in OS, and the CEP55 expression level in OS was correlated with metastasis and poor prognosis. Through in vitro experiments, we confirmed that CEP55 knockdown significantly induced cell cycle arrest at G1 phase and suppressed OS cell proliferation, migration and invasion. In addition, CEP55 knockdown suppressed OS tumour growth in nude mice. Global gene expression profiling of CEP55-silenced MNNG/HOS cells showed that the AKT pathway might be involved in the regulation of OS cell activity. Two downstream factors of AKT signalling, CCND1 and FN1, were found to have significantly higher expression in tumour tissues, and their mRNA expression levels were strongly correlated with CEP55 expression. To conclude, our data suggest that CEP55 can be used as a prognostic marker for OS, highlighting the significance of CEP55 signalling as a putative therapeutic target.

Rh(III)-catalyzed C(sp3)–H bond aminocarbonylation of 8-methylquinolines and isocyanates has been realized under mild conditions. This approach is applicable to different aryl and alkyl isocyanates, leading to the synthesis of various α-quinolinyl amide compounds in moderate to excellent yields. A plausible mechanism for this transformation is proposed according to the experimental results obtained.

The present study aimed to isolate and characterize side population (SP) cells in the human lung cancer A549 cell line, and elucidate the molecular mechanism of SP cells underlying lung cancer. The SP and non-SP (NSP) cells in A549 cells were isolated and their differentiation was analyzed by fluorescence-activated cell sorting. An in vitro plate clone assay, Matrigel® Transwell assay and chemoresistance analysis of the sorted SP and NSP cells were performed. In addition, the sorted SP and NSP cells were injected into BALB/c nude mice to detect their tumorigenic potential in vivo. The expression of ATP-binding cassette sub-family G member 2 (ABCG2) in transplanted tumors was detected by immunohistochemistry. The SP and NSP cells were successfully isolated. The results demonstrated that SP cells accounted for 1.09% of live A549 cells. SP cells produced SP and NSP cells, while NSP cells only produced NSP cells. In addition, SP cells formed more colonies, exhibited improved invasive ability and increased levels of chemoresistance compared with NSP cells in vitro. SP cells demonstrated a higher tumorigenic potential in BALB/c nude mice, and the number of ABCG2-positive cells in the SP xenograft tumors were significantly increased compared with that in the NSP xenograft tumors. The present study indicated that SP cells isolated from the human lung cancer A549 cell line demonstrated increased tumorigenicity, and improved invasive ability and chemoresistance compared with NSP cells. In addition, detection of ABCG2 expression may assist in predicting the chemotherapeutic outcome of patients, and serve as a target for treating lung cancer.

As a generalization of the class of inverse semigroups, the class of Ehresmann semigroups is introduced by Lawson and investigated by many authors extensively in the literature. In particular, Gomes and Gould construct a fundamental Ehresmann semigroup CE from a semilattice E which plays for Ehresmann semigroups the role that TE plays for inverse semigroups, where TE is the Munn semigroup of a semilattice E. From a varietal perspective, Ehresmann semigroups are derived from reduction of inverse semigroups. In this paper, from varietal perspective Ehresmann semigroups are extended to generalized Ehresmann semigroups derived instead from normal orthodox semigroups (i.e. regular semigroups whose idempotents form normal bands) with an inverse transversal. We present here a semigroup C(I,Λ,E∘) from an admissible triple (I, Λ, E∘) that plays for generalized Ehresmann semigroups the role that CE from a semilattice E plays for Ehresmann semigroups. More precisely, we show that a semigroup is a fundamental generalized Ehresmann semigroup whose admissible triple is isomorphic to (I, Λ, E∘) if and only if it is (2,1,1,1)-isomorphic to a quasi-full (2,1,1,1)-subalgebra of C(I,Λ,E∘). Our results generalize and enrich some results of Fountain, Gomes and Gould on weakly E-hedges semigroups and Ehresmann semigroups.

Osteosarcoma is the most common bone tumor affecting both adolescents and children. Early detection is critical for the effective treatment of the disease. Derived from cancer cells, miR‑21 contained within exosomes in the tumor microenvironment may act on both cancer cells and the surrounding tumor microenvironment (TME), including immune cells, endothelial cells and fibroblasts. In human serum and plasm, the level of exosomal miR‑21 between osteosarcoma patients and healthy controls differs, supporting the role of miR‑21 as a biomarker for osteosarcoma. The involvement of a number of miR‑21 target genes in tumor progression suggests that miR‑21 may significantly affect the plasticity of cancer cells, leading to tumor progression, metastasis, angiogenesis and immune escape in osteosarcoma. Understanding the biogenesis and functions of exosomal miR‑21 is of great value for the diagnosis and therapy of cancer, including osteosarcoma. The present review discusses the role of miR‑21 in the tumor microenvironment, and in the development and progression of osteosarcoma, with an aim to summarize the functions of this miRNA in cancer.

Variant rs7034162 in NFIB was reported to be associated with metastasis of osteosarcoma in European cases with genome-wide significance. Our purpose was to replicate the association of rs7034162 with the metastasis of osteosarcoma in the Chinese population and to further characterize the expression level of NFIB in osteosarcoma tissues. A total of 321 patients were included in this study. Variant rs7034162 was genotyped for each patient using the Taqman genotyping assay. Fifty-two cases of tumor tissues and adjacent normal tissues were collected during surgery. The χ2 test was used to investigate the association of rs7034162 with the metastasis of osteosarcoma. The Student t test was used to compare the gene expression between patients with metastasis and those without metastasis. The messenger RNA expression level of NFIB was then compared among different genotypes of rs7034162 with 1-way analysis of variance test. Ninety-three patients were found to have metastasis. Patients with genotype AA had remarkably higher incidence of metastasis than those with genotype TT (34.4% vs 17.1%, P = .002). Patients with metastasis were found to have significantly higher rate of allele A than those without metastasis (53.2% vs 43.9%, P = .03). The messenger RNA expression of NFIB was significantly lower in tumor tissues of patients with metastasis than in those without metastasis (0.00035 ± 0.00017 vs 0.00063 ± 0.0025, P < .001). Compared to patients with genotype TT, those with genotype AA had remarkably decreased expression of NFIB (0.00033 ± 0.0014 vs 0.00067 ± 0.00037, P = .01). Single-nucleotide polymorphism rs7034162 was associated with metastasis of osteosarcoma in the Chinese population possibly via downregulation of NFIB. Further network analyses revealing the related pathways can help elucidate the molecular mechanism of distant metastasis in patients with osteosarcoma.

Photocatalytic degradation based on semiconductor is a potential technology for water pollution treatment by utilizing light irradiation. As a new p-type semiconductor material, CuBi2O4 is favored by researchers due to its excellent photocatalytic properties. Herein, a group of CuBi2O4 nanospheres were synthesized by simple hydrothermal method, in which the formation and transformation process of CuBi2O4 microsphere structure was studied by adjusting the hydrothermal reaction time. On this basis, a series Z-Scheme heterojunctions with different mass ratios of CuBi2O4/CdMoO4 nanocomposites were constructed and the formation mechanism of Z-scheme heterojunction was described detailedly. The results of the study confirmed that CuBi2O4/CdMoO4 (10 %) composites exhibited excellent photocatalytic activity, with a high degradation rate of 95.36 % for MB under visible light irradiation, by comparison with bare CuBi2O4 and CdMoO4. In order to improve the quantum efficiency, doping CdMoO4 onto CuBi2O4 greatly improved the surface charge migration rate of CuBi2O4 and reduced the rate of electron-hole pairs recombination. The degradation rate of CuBi2O4/CdMoO4 (10 %) remained over 85 % after three times cycling experiments, demonstrating that the heterojunction has good repeatability and stability. The free radical trapping experiments demonstrated that the h+ and O2– were the main substances involved in photocatalytic oxidation-reduction, which match the energy band, and was consistent with the mechanism of Z-Scheme heterojunctions. This study stated that establishment of a novel CuBi2O4/CdMoO4 heterojunction composite photocatalyst is a new ideal way to carry out environmental pollution treatment and clean energy.

A pair of enantioselective switchable bifunctional catalysts are shown to promote a range of conjugate addition reactions in up to 95 : 5 e.r. and 95% conversion. Each catalyst can be switched OFF using conditions that switch the other catalyst ON. Catalyst ON : OFF ratios of up to 98 : 2 and 1 : 99 were achieved, with a ratio of reaction rates of up to 16 : 1 between the ON and OFF states, maintained over complete ON–OFF–ON and OFF–ON–OFF cycles. However, simultaneous operation of the catalyst pair in the same reaction vessel, which in principle could allow product handedness to be switched by simple E–Z isomerisation of the catalyst pair, was unsuccessful. In this first generation complementary pair of enantioselective switchable organocatalysts, the OFF state of one catalyst inhibits the ON state of the other.

Thiostrepton (TSR), an archetypal bimacrocyclic thiopeptide antibiotic that arises from complex posttranslational modifications of a genetically encoded precursor peptide, possesses a quinaldic acid (QA) moiety within the side-ring system of a thiopeptide-characteristic framework. Focusing on selective engineering of the QA moiety, i.e., by fluorination or methylation, we have recently designed and biosynthesized biologically more active TSR analogs. Using these analogs as chemical probes, we uncovered an unusual indirect mechanism of TSR-type thiopeptides, which are able to act against intracellular pathogens through host autophagy induction in addition to direct targeting of bacterial ribosome. Herein, we report the accumulation of 6'-fluoro-7', 8'-epoxy-TSR, a key intermediate in the preparation of the analog 6'-fluoro-TSR. This unexpected finding led to unveiling of the TSR maturation process, which involves an unusual dual activity of TsrI, an α/β-hydrolase fold protein, for cascade C-N bond cleavage and formation during side-ring system construction. These two functions of TsrI rely on the same catalytic triad, Ser72-His200-Asp191, which first mediates endopeptidyl hydrolysis that occurs selectively between the residues Met-1 and Ile1 for removal of the leader peptide and then triggers epoxide ring opening for closure of the QA-containing side-ring system in a regio- and stereo-specific manner. The former reaction likely requires the formation of an acyl-Ser72 enzyme intermediate; in contrast, the latter is independent of Ser72. Consequently, C-6' fluorination of QA lowers the reactivity of the epoxide intermediate and, thereby, allows the dissection of the TsrI-associated enzymatic process that proceeds rapidly and typically is difficult to be realized during TSR biosynthesis.

In this paper, we study battery capacity design for battery electric vehicles (BEVs). The core of such design problems is to find a good tradeoff between minimizing the capacity to reduce financial costs of drivers and increasing the capacity to satisfy daily travel demands. The major difficulty of such design problems lies in modeling the diversity of daily travel demands. Based on massive trip records of taxi drivers in Beijing, we find that the daily vehicle miles traveled (DVMT) of a driver (e.g., a taxi driver) may change significantly in different days. This investigation triggers us to propose a mixture distribution model to describe the diversity in DVMT for various driver in different days, rather than the widely employed single distribution model. To demonstrate the merit of this new model, we consider value-at-risk and mean-variance battery capacity design problems for BEV, with respect to conventional single and new mixture distribution models of DVMT. Testing results indicate that the mixture distribution model better leads to better solutions to satisfy various drivers.

Rh(III)-catalyzed C(sp

Through investigating and comparing the fatigue behavior of an as-cast Mg–7%Gd–5%Y–1%Nd–0.5%Zr alloy in both laboratory air and 3.5 wt.% NaCl solution, the effect of corrosion attack on fatigue crack initiation has been disclosed. The S–N curves showed that the fatigue strength in air was 120 MPa and not sensitive to the loading frequency, whereas the fatigue strength in NaCl solution decreased from 80 MPa to 60 MPa with the loading frequency decreasing from 20 Hz to 5 Hz. Observations to fracture surfaces demonstrated that in air, fatigue cracks preferentially initiated at the oxide inclusions. However, the fatigue crack initiation in NaCl solution was associated with corrosion pits. Moreover, multiple fatigue cracks initiated at pits on fracture surfaces of corrosion fatigue failed samples when the loading frequency decreased to 5 Hz. Based on the measured “defect area” of oxide inclusions, the predicted fatigue strength in air could be well fitted with the experimental data. However, due to the occurrence of hydrogen embrittlement and crack initiation at multiple sites, the fatigue strength of samples tested in NaCl solution cannot be predicted. Keywords: Mg alloy, Corrosion, Cyclic loading, Fatigue crack initiation, Fatigue behavior